package authentication.token;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import org.apache.commons.codec.binary.Base64;

/**
 * @author yuqi<307530884@qq.com> <2017/3/28>
 * @version 1.0
 * @since 1.0
 */
public class AES {

    // 加密
    public static String encrypt(String sSrc, String sKey) {
        if (sKey == null) {
            System.out.println("Key为空null");
            return null;
        }
        // 判断Key是否为16位
        if (sKey.length() != 16) {
            System.out.println("Key长度不是16位");
//            return null;
        }

        try {
            byte[] raw = sKey.getBytes();
            SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");//"算法/模式/补码方式"
            IvParameterSpec iv = new IvParameterSpec("0102030405060708".getBytes());//使用CBC模式，需要一个向量iv，可增加加密算法的强度
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);
            byte[] encrypted = cipher.doFinal(sSrc.getBytes());

            return Base64.encodeBase64String(encrypted);//此处使用BAES64做转码功能，同时能起到2次加密的作用。
        } catch (Exception e) {
            e.printStackTrace();
            throw new RuntimeException("ase encrypt error");
        }
    }

    // 解密
    public static String decrypt(String sSrc, String sKey) {
        try {
            // 判断Key是否正确
            if (sKey == null) {
                System.out.print("Key为空null");
                return null;
            }
            // 判断Key是否为16位
            if (sKey.length() != 16) {
                System.out.print("Key长度不是16位");
                return null;
            }
            byte[] raw = sKey.getBytes("ASCII");
            SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            IvParameterSpec iv = new IvParameterSpec("0102030405060708"
                    .getBytes());
            cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);
            byte[] encrypted1 = Base64.decodeBase64(sSrc);//先用bAES64解密
            try {
                byte[] original = cipher.doFinal(encrypted1);
                String originalString = new String(original);
                return originalString;
            } catch (Exception e) {
                System.out.println(e.toString());
                return null;
            }
        } catch (Exception ex) {
            System.out.println(ex.toString());
            throw new RuntimeException("ase decrypt error");
        }
    }

}
